The 23-year-old featured 24 times and netted seven goals for Chesterfield during a loan stint at the beginning of last season.
He later spent time on loan at League One side Leyton Orient, where he scored three goals in 17 appearances.
“I’m absolutely delighted — it really feels like coming home,” Markanday told the club’s official website.
“I’m happiest when I’m out on the pitch, and there’s no better place than here to help me do that.”
Markanday becomes Chesterfield’s first signing following their League Two play-off defeat to Walsall.